An endoscope apparatus includes an endoscope and processing circuitry. The endoscope includes an imaging device disposed at a distal end of an insertion portion and configured to capture endoscopic images when the endoscope is inserted into a human body. The processing circuitry is configured to determine, based on image changes of the endoscopic images, whether each endoscopic image is a non-observation target image or an observation target image, detect a specific region based on image characteristics in endoscopic images determined as the non-observation target images, determine images including the specific region among the non-observation target images as correction target images, determine a directional relationship between a direction of the imaging device and an anatomical orientation of the human body, based on the correction target images, and perform direction standardization processing based on the directional relationship, thereby standardizing orientations of the correction target images based on the anatomical orientation.